Tuesday, July 3, 2012

Why Do Consumers Buy Organic?

Though organic foods generally cost more than conventionally grown foods, sales of organic fruits and vegetables in the United States have nearly doubled in the past five years (OTA).  Why are the sales of organic foods continuing to grow? 

People prefer organics for a variety of reasons, including: the belief that they are healthier, pesticide-free, more nutritious, environmentally-friendly, taste better, not genetically-modified (GMO), supportive of small farmers and rural communities, the right thing to do ethically, and a vote against modern farming methods (nielsenwire).


Are Organic Foods Healthier?
Some experts say that organic foods don’t provide any more nutritional value than foods grown conventionally. Other experts disagree. What they do agree on, though, is that with organic agriculture, chemicals are not used in the environment that could leach into water supplies and animals aren’t given hormone or medicinal treatments that end up in their milk or meat. Shoppers can be assured that when they choose foods with the USDA Organic Label, these edibles are produced using environmentally-friendly practices that pose low health risks for consumers.

Do Our Foods Contain Pesticide Residues?
One of the most often cited reasons for buying organic is to avoid dietary pesticide exposure.  Organic consumers are willing to pay more for organic foods in order to reduce the toxic load: to keep chemicals out of the air, water, soil and our bodies.  Many consumers believe that buying organic food promotes a less toxic environment for all living things (Organic.org).
USDA PESTICIDE DATA PROGARM TESTS FOODS FOR PESTICIDE CONTAMINATION
To estimate pesticide contamination of foods purchased by consumers, the Department of Agriculture’s Pesticide Data Program (PDP) samples more than 80 types of fruits, vegetables, nuts, meat, grains, dairy products, and other foods to identify and quantify residues from insecticides, herbicides, fungicides, and growth regulators. The foods, including processed and imported products, are collected from 10 states representing all regions of the country; the samples are collected as close to the point of Consumption as possible.  Fruit and vegetable samples are collected at terminal markets and large chain store distribution centers from which food commodities are supplied to supermarkets and grocery stores. Sampling at these locations allows for residue measurements that include pesticides applied during crop production and those applied after harvest (such as fungicides and growth regulators, such as sprouting inhibitors) and takes into account residue degradation while food commodities are in storage.

Prior to testing, PDP analysts wash samples for 10 seconds with gently running cold water as a consumer would do; no chemicals, soap or any special wash are used.   This provides an accurate assessment of what consumers actually ingest.

MOST CONVENTIONALLY GROWN FOOD IS CONTAMINATED WITH PESTICIDES
In its 2008 report, PDP analyzed 11,683 samples, conducting an average of 105 tests on each sample (more than 1.22 million analyses in total). Only 23.1 percent of samples had zero pesticide residues detected, 29.5 percent had one residue, and the remainder had two or more. The majority of residues detected were at levels far below EPA tolerances (limits on pesticide residues on foods; referred to as maximum residue limits, or MRLs, in many other countries) but the data on which the tolerances are based are heavily criticized by environmental health professionals and advocates as being inadequate and unduly influenced by industry (President’s Cancel Panel Report 2008-2009).

The 2010 PDP data indicate that 41.0 percent of all food samples tested contained no detectable pesticides, 18.5 percent contained 1 pesticide, and 40.5 percent contained more than 1 pesticide. Parent compounds and their metabolites are combined to report the number of “pesticides” rather than the number of “residues”.

What About Baby Foods?
The 2010 PDP report contained data on three baby foods for the first time:  pears, green beans and sweet potatoes. In general, the sweet potatoes and pears were pretty clean, but 9% of the green bean samples had clearly unacceptable levels of the organophosphate insecticide methamidophos. A remarkable 25% of pear baby food samples contained six or more residues, and 3.7% of the samples contained 10 residues. Not good. As always, buy organic (The Organic Center))!

Bee Killing Insecticides
Nicotinyl insecticide residues are extremely common because they are widely used and are systemic – they work by moving into the plant, including the harvested portion. In fact, about 1 in 10 of samples tested by the PDP (across ALL crops) had residues of imidacloprid (Admire), and many fresh fruit and vegetable samples contained residues of two nictoinyls. This is the family of insecticides implicated in honey bee Colony Collapse Disorder (The Organic Center)).

Drinking Water
Extensive testing was carried out on drinking water, including school wells. These data have some surprises– especially the fact that 85% of finished drinking water had residues of 2,4-D. This phenoxy herbicide is known to be a significant risk factor for a host of reproductive problems, birth defects, and cancers. It is also linked to a possible, new herbicide-tolerant, genetically engineered corn variety currently under review by the USDA and EPA (The Organic Center).

Atrazine (another endocrine disrupting herbicide linked to breast cancer and a host of developmental abnormalities) was found in 95%+ of samples of drinking water! The levels are generally very low, but this year’s PDP confirms that most people living in heavily farmed regions are ingesting three, four or more herbicides daily via finished drinking water (The Organic Center)).

How Do Pesticide Residues on Organic Foods Compare with those on Conventionally Grown Foods?
The PDP survey also includes organic samples. Just as in recent years, the organically grown food tested by PDP in 2010 has substantially fewer residues. When residues are detected, the levels are usually 10-X to 100-X lower than in conventional samples. Based on TOC’s “Dietary Risk Index,” typical risk levels in organic foods are 50-200 times lower than in the corresponding conventional foods. Clearly, consumers purchasing organic food to lower pesticide exposures and risks are getting just that (http://www.generationsoforganic.org/news/latest-news/2010pdpdatablog/).

Baker, et al. conducted an analysis of pesticide residue data to determine and compare the differences between organically grown and non-organic fresh fruits and vegetables. Data on residues in foods from three different market categories (conventionally grown, integrated pest management (IPM)-grown/no detectable residues (NDR), and organically grown) were compared using data from three test programs: The Pesticide Data Program of the US Department of Agriculture; the Marketplace Surveillance Program of the California Department of Pesticide Regulation; and private tests by the Consumers Union, an independent testing organization. Organically grown foods consistently had about one-third as many residues as conventionally grown foods, and about one-half as many residues as found in IPM/NDR samples. Conventionally grown and IPM/NDR samples were also far more likely to contain multiple pesticide residues than were organically grown samples. Comparison of specific residues on specific crops found that residue concentrations in organic samples were consistently lower than in the other two categories, across all three data sets. The IPM/NDR category, based on data from two of the test programs, had residues higher than those in organic samples but lower than those in conventionally grown foods.

Are these pesticide residues harmful to our health?
The Organic Center reports that new science published in the last five years has established strong linkages between prenatal pesticide exposures and developmental problems in infants and children (Bouchard et al., 2010), especially cognitive deficits
(Rauh et al., 2011; Engel et al., 2011; Bouchard et al., 2011; Marks et al., 2010), smaller brains (Whyatt et al., 2004), reproductive problems (Christiansen et al., 2009), asthma (Hernandez et al., 2011) and increased risk of overweight (Adigun et al., 2010) and diabetes (Lim et al., 2009). Emerging science has both reinforced long simmering
concerns over pesticides and created new worries, especially those linking pesticides to overweight and type 2 diabetes (Patel et al., 2010).

A 2010 study has shown that children with higher levels of organophosphate pesticide metabolites in their urine are more likely to have attention deficit hyperactivity disorder.

On April 21, 2011 the highly regarded journal Environmental Health Perspectives published online the results of three studies carried out at three different universities, using three different methods exploring the same phenomenon – the impacts of prenatal exposures to organophosphate (OP) insecticides on the neurological development of children.  The three studies reached the same, sobering conclusion – exposure to OPs during pregnancy leads to IQ deficits in school-age children.

The December 2011 issue of Environmental Health Perspectives Dr. David Belinger reported that three common environmental chemicals – lead, organophosphate pesticides and methylmercury – may have effects on children's IQ in the overall population equaling or exceeding those of major medical conditions such as preterm birth or ADHD – two of the most prevalent health problems in U.S. children.  He concluded that when population impact is considered, the contributions of chemicals to FSIQ (full scale IQ points) loss in children are substantial, primarily due to the relative ubiquity of exposure.

The most recent publication of Environmental Health Perspectives, July 02, 2012, contained the results of a non-invasive magnetic resonance imaging (MRI) study which reveals that in children exposed to the organophosphate insecticide chlorpyrifos (CPF) in utero, CPF alters the structure of brain regions that govern a broad range of behavioral outcomes, offering new insight into the way in which CPF affects the central nervous system of exposed fetuses.  They found that brain damage occurs at exposure levels well below current EPA dietary reference dose levels indicating that the EPA risk assessment for CPF needs to be revised.
For adults, pesticide risk assessment can rarely prove definitively a direct, causal relationship between pesticide exposure and a specific adverse health outcome that some individual has suffered. But across the population, scientists have concluded that pesticide exposure is a risk factor that increases the chances that certain health problems will occur with greater frequency and/or lead to more serious consequences (TOC).

The public will continue to hear conflicting claims about whether there is any
reason to worry about pesticide residues in the diet. While scientists work toward
more complete and accurate pesticide dietary risk assessments, reducing
pesticide exposures across the population remains a sure way to reduce pesticide
risks, whatever those risks ultimately prove to be (TOC).

President’s Panel on Cancer Report:
The 2008-2009 President’s Panel on Cancer Report, titled:  REDUCING  ENVIRONMENTAL CANCER RISKWhat We Can Do Now, was very direct about the dangers of exposure to dietary pesticides:

“Despite overall decreases in incidence and mortality, cancer continues to shatter and steal the lives of Americans. Approximately 41 percent of Americans will be diagnosed with cancer at some point in their lives, and about 21 percent will die from cancer. The incidence of some cancers, including some most common among children, is increasing for unexplained reasons.”

Recommendations:  What Individuals Can Do:

Individuals and families have many opportunities to reduce or eliminate chemical exposures.  Exposure to pesticides can be decreased by choosing, to the extent possible, food grown without chemical pesticides or fertilizers and washing conventionally grown produce to remove residues.  Similarly, exposure to antibiotics, growth hormones, and toxic run-off from livestock feed lots can be minimized by eating free-range meat raised without these medications if it is available.  Avoiding or minimizing consumption of processed, charred, and well-done meats will reduce exposure to carcinogenic heterocyclic amines and polyaromatic hydrocarbons”.

Nearly 1,400 pesticides have been registered (i.e., approved) by the Environmental Protection Agency (EPA) for agricultural and non-agricultural use. Exposure to these chemicals has been linked to brain/central nervous system (CNS), breast, colon, lung, ovarian (female spouses), pancreatic, kidney, testicular, and stomach cancers, as well as Hodgkin and non-Hodgkin lymphoma, multiple myeloma, and soft tissue sarcoma. Pesticide-exposed farmers, pesticide applicators, crop duster pilots, and manufacturers also have been found to have elevated rates of prostate cancer, melanoma, other skin cancers, and cancer of the lip (PCP Report).
Approximately 40 chemicals classified by the International Agency for Research on Cancer (IARC) as known, probable, or possible human carcinogens, are used in EPA-registered pesticides now on the market. Some of these chemicals are used in several different pesticides; for example, chromium trioxide, an IARC Class 1 carcinogen (carcinogenic to humans), is used in 14 different pesticide products from five different companies. Thus, the total number of registered pesticide products containing known or suspected carcinogens is far greater than 40, but few have been severely restricted in the United States. Among those that have been banned, or had their use restricted, are DDT, ethylene oxide, dimethlhydrazine, hexachlorobenzene, and some chlorophenoxy herbicides (PCP Report).

While all Americans now carry many foreign chemicals in their bodies, women often have higher levels of many toxic and hormone-disrupting substances than do men. Some of these chemicals have been found in maternal blood, placental tissue, and breast milk samples from pregnant women and mothers who recently gave birth. Thus, chemical contaminants are being passed on to the next generation, both prenatally and during breastfeeding. Some chemicals indirectly increase cancer risk by contributing to immune and endocrine dysfunction that can influence the effect of carcinogens (PCP Report).

Children of all ages are considerably more vulnerable than adults to increased cancer risk and other adverse effects from virtually all harmful environmental exposures. In addition, some toxics have adverse effects not only on those exposed directly (including in utero), but on the offspring of exposed individuals (PCP Report).

Some scientists maintain that current toxicity testing and exposure limit-setting methods fail to accurately represent the nature of human exposure to potentially harmful chemicals. Current toxicity testing relies heavily on animal studies that utilize doses substantially higher than those likely to be encountered by humans. These data—and the exposure limits extrapolated from them—fail to take into account harmful effects that may occur only at very low doses. Further, chemicals typically are administered when laboratory animals are in their adolescence, a methodology that fails to assess the impact of in utero, childhood, and lifelong exposures. In addition, agents are tested singly rather than in combination (PCP Report).

The prevailing regulatory approach in the United States is reactionary rather than precautionary. That is, instead of taking preventive action when uncertainty exists about the potential harm a chemical or other environmental contaminant may cause, a hazard must be incontrovertibly demonstrated before action to ameliorate it is initiated. Moreover, instead of requiring industry or other proponents of specific chemicals, devices, or activities to prove their safety, the public bears the burden of proving that a given environmental exposure is harmful (PCP Report).

By comparison, the European Union adopted the precautionary principle which, in essence, directs that action be taken to reduce risk from chemicals in the face of uncertain but suggestive evidence of harm to human health and the environment. While the system is far from perfect (see, for example, RoundUp and Birth Defects, Is the Public Being Kept In The Dark?, a report by international scientists challenging the European pesticide approval process for failing to consider independent scientific research and the lack of regulatory enforcement), there is, nonetheless, a formal process which allows for the removal from the market of chemicals suspected of causing harm, even when scientific evidence is insufficient, inconclusive or uncertain but preliminary scientific evaluation indicates that there are reasonable grounds for concern (http://gmo-journal.com/index.php/2011/10/25/are-systemic-pesticides-to-blame-for-honeybee-colony-collapse/).

The President’s Cancer Panel recommended “The adoption of a new precautionary, prevention-oriented approach to replace our current reactionary approaches in which human harm must be proven before action is taken to reduce or eliminate exposure.  As a part of this approach, it is recommended that the burden of proof of safety should be shifted to the manufacturer, rather than the current burden of proof being upon the government to prove harm.

The entire U.S. population is exposed on a daily basis to numerous agricultural chemicals, some of which also are used in residential and commercial landscaping. Many of these chemicals have known or suspected carcinogenic or endocrine-disrupting properties. Pesticides (insecticides, herbicides, and fungicides) approved for use by the U.S. Environmental Protection Agency (EPA) contain nearly 900 active ingredients, many of which are toxic. Many of the solvents, fillers, and other chemicals listed as inert ingredients on pesticide labels also are toxic, but are not required to be tested for their potential to cause chronic diseases such as cancer. In addition to pesticides, agricultural fertilizers and veterinary pharmaceuticals are major contributors to water pollution, both directly and as a result of chemical processes that form toxic by-products when these substances enter the water supply. Farmers and their families, including migrant workers, are at highest risk from agricultural exposures. Because agricultural chemicals often are applied as mixtures, it has been difficult to clearly distinguish cancer risks associated with individual agents (PCP Report).

Meaningful measurement and assessment of the cancer risk associated with many environmental exposures are hampered by a lack of accurate measurement tools and methodologies. This is particularly true regarding cumulative exposure to specific established or possible carcinogens, gene-environment interactions, emerging technologies, and the effects of multiple agent exposures. Single-agent toxicity testing and reliance on animal testing are inadequate to address the backlog of untested chemicals already in use and the plethora of new chemicals introduced every year. Some high-throughput screening (HTS) technologies are available to enable testing of many chemicals and other contaminants simultaneously, but many remain to be developed to meet chemical testing needs (PCP Report).

Recognizing that results of laboratory and animal studies do not always predict human responses, an environmental health paradigm for long-latency diseases is needed to enable regulatory action based on compelling animal and in Revitro evidence before cause and effect in humans has been proven (PCP Report).

Industry has exploited regulatory weaknesses, such as government’s reactionary (rather than precautionary) approach to regulation. Likewise, industry has exploited government’s use of an outdated methodology for assessing “attributable fractions” of the cancer burden due to specific environmental exposures. This methodology has been used effectively by industry to justify introducing untested chemicals into the environment (PCP Report).

Atrazine is a broad leaf herbicide that has become ubiquitous in the population. Used primarily in corn production, approximately 80 million pounds of atrazine are applied annually in the U.S.—more than any other agricultural pesticide.  Atrazine is used to increase crop yields by preventing weeds from growing and stealing nutrients from the crop, but some evidence suggests that eliminating its use would have little impact on usable crop levels.

Atrazine has been shown to affect mammary gland development in animal studies, with some findings suggesting multigenerational effects. The relatively few human studies of atrazine carcinogenicity have been inconclusive. IARC has classified atrazine as a group 3 human carcinogen (not classifiable as to its carcinogenicity). EPA has faced considerable criticism from the media and environmental groups on its oversight of atrazine and 2003 renewal of atrazine’s classification as “not likely to cause cancer in humans.” In October 2009, EPA announced a comprehensive reevaluation of atrazine’s cancer and non-cancer effects based on the latest scientific data. The evaluation is expected to be completed in September 2010; EPA will determine at that time whether the agency’s regulatory position on atrazine should be revised and if new restrictions are needed to better protect health and the public.

{We use 80 million pounds [of atrazine] annually in the United States. It’s the number-one pesticide contaminant of ground water, surface water, and drinking water. It’s used in more than 80 countries but it’s now outlawed in all of Europe or, as the company likes to say, has been denied regulatory approval. The main point here is that here’s a compound that we use 80 million pounds of, and it’s illegal in the home country of the company that makes it.}  Tyrone Hayes, University of California, Berkeley. 

The Problem With Systemic Pesticides
James Frazier, Ph.D, a professor of entomology at Penn State’s College of Agricultural Sciences, and other researchers and beekeepers are concerned that the EPA is not adequately evaluating pesticide interaction, sub-lethal impacts, and interaction with other stressors on honeybee fitness.  Like Tom Theobald, a Colorado beekeeper and one of the founders of the Boulder County Beekeepers’ Association, Professor Frazier criticized the EPA for using the same approach to evaluating systemic pesticides that is used for older generation pesticides. He explained to me in a recent interview that the EPA had sixteen years to develop a different protocol for evaluating systemic pesticides but the agency still relies on a risk-benefits analysis model it has used all along. Under the risk-benefits analysis, scientific evidence is only one of the factors considered when evaluating a pesticide for approval. The other factors include economic, technological, political, and social. Another serious problem with the EPA approval process is that ultimately it is the EPA administrators, not the EPA scientists, who make approval decisions.

Systemic pesticides call out for a different system of approval since they differ in many respects from older generation pesticides.

Being one of the most widely used pesticides in the United States, systemic pesticides became popular in U.S. in 2000s and have increased with the increased planting of transgenic seeds (a.k.a. GMOs). “Unlike older pesticides that evaporate or disperse shortly after application, neonicotinoids are systemic poisons. Applied to the soil or doused on seeds, neonicotinoid insecticides incorporate themselves into the plant’s tissues, turning the plant itself into a tiny poison factory emitting toxin from its roots, leaves, stems, pollen, and nectar.”  With systemic pesticides, “the chemical is in the bloom. So bees searching for nectar now can come into contact with pesticides too.”

And they persist in the soil for longer than the older generation pesticides. Professor Frazier explained that systemic pesticides could remain in the soil anywhere between two to three years, and in some cases up to six years, depending on the nature of the soil and the chemical formulation of the pesticide.

Systemic pesticides are of a particular concern to beekeepers because they kill sucking and chewing insects by disrupting their nervous systems. While the routes of exposure have previously focused on contaminated food that is taken up by bees, new evidence is emerging that suggests additional ways in which bees are exposed to neonicotinoids. Recent studies performed in Italy suggest that bees become contaminated by insecticide (neonicotinoid) dust emission during foraging activity when they fly near a drilling machine at levels “sufficient to kill the bees.” Specifically, the researchers concluded that their trials “indicate that when a bee travelling towards a food source flies over a seeder that is sowing insecticide-coated maize seed, the bee may be exposed to a lethal dose of active ingredient, probably even in a single flight.” (Marzaro, et al., 2011; APENET Project, 2011).

Take Home Lesson?
Use the precautionary principle and eat organic when you can.  If you can’t buy all of your fruits and vegetables in organic and you can’t grow your own, then use the Environmental Working Group’s Dirty Dozen List as a guide to which foods are most important to eat organic in order to avoid dietary pesticide exposure.


Monday, June 18, 2012


EPM
(Ecological Pest Management)


What is Ecological Pest Management?
Ecological Pest Management (EPM) is also called biointensive IPM.  EPM originated from Integrated Pest Management (IPM) and shares many of the same components as conventional IPM, including monitoring, use of economic thresholds, record keeping, and planning.  An important difference between conventional and biointensive IPM, however, is that the emphasis of the latter is on proactive measures to redesign the agricultural ecosystem to the disadvantage of a pest and to the advantage of its parasite and predator complex (ATTRA).

Pest management is an ecological matter. The size of a pest population and the damage it inflicts is, to a great extent, a reflection of the design and management of a particular agricultural ecosystem.  The design and management of our agricultural systems need re-examining. We’ve come to accept routine use of biological poisons in our food systems as normal.  Attempting to implement an ecology-based discipline like IPM in large monocultures, which substitute chemical inputs for ecological design, can be an exercise in futility and inefficiency (ATTRA).

According to ATTRA, IPM, as it was originally conceived, proposed to manage pests though an understanding of their interactions with other organisms and the environment.  However, IPM has strayed from its ecological
roots. Critics of what might be termed “conventional” IPM note that it has been implemented as Integrated Pesticide Management (or even Improved Pesticide Marketing) with an emphasis on using pesticides as a tool of first resort. What has been missing from this approach, which is essentially reactive, is an understanding of the ecological basis of pest infestations. Also missing from the conventional approach are guidelines for ecology-based manipulations of the farm agroecosystem that address the questions:

Ø  Why is the pest there?
Ø  How did it arrive?
Ø  Why doesn’t the parasite/predator complex control the pest?

Guidelines for ecology-based manipulations of the farm agroecosystem:


For more information on biointensive integrated pest management strategies visit the National Sustainable Agriculture Information website and click on:

Dr. Mcbug’s website (see information below) is a very good resource for EPM. 

Another good resource is:  Farmscaping to Enhance Biological Control
  
A first step in ecological pest management is learn more about pests and beneficial insects that may be present in your fields.  The Alabama IPM Communicator contains some valuable information about which pests are present in AL crops and this week Dr. Ayanava Majumdar, Extension Entomologist, begins a series about insect predators:  Know Your Friends:  Alabama IPM Communicator, June 15, 2012. Volume 3, No. 8:

Every week I will post organic-relevant information from the Alabama IPM Communicator. 

Below is the excerpt from this week’s newsletter:
KNOW YOUR FRIENDS:
INSECT PREDATORS—LACEWINGS & LADY BEETLES
By Dr. Ayanava Majumdar
Beneficial insects are an important part of the natural ecosystem and provide a valuable service to crop producers. An acre of crops can have a significantly large number of insect predators and parasites (in fact, according to published scientific literature from Arkansas and California, there can be more species of beneficial insects present in a cropping system than pest species). However, low populations and cryptic behaviors of predators make them appear as if they are ineffective. Through this newsletter section called “Know Your Friends”, I will attempt to familiarize readers with one or two beneficial insect species in every issue and explain their field usage technique as recommended by the industry. Organic as well as conventional farmers should use selective insecticides in a timely manner to minimize impact on the beneficial insect populations.

Sources of beneficial insects:
Numerous vendors sell beneficial insects via their website along with plenty of good information. For example, Arbico Organics (AZ), Orcon (CA), Grow Organic (CA), Gardens Alive (IN), and Nature’s Control (OR) sell insect predators in large numbers and at least one vendor sells it as a ‘beneficial insect program’ with weekly shipments adjusted to your pest control needs. Note that beneficial insects are slow-acting in pest outbreak situation, so use beneficial insects preventively when pests are in low populations and have not overwhelmed the crops you are trying to protect. Follow the release instructions that come with the products and modify your spray schedule to adjust for the presence of beneficial insects.

[Note:   The Beneficial Insect Company in NC is another source for beneficial insects.

GREEN LACEWINGS
Many species of lacewings occur naturally in cropping systems. Green and brown lacewings are most common predators of aphids, so they are also known as the ‘aphid-lions’. Green lacewings are larger in size than brown lacewings. Lacewing adults lay eggs singly or in small groups attached to various plant parts. Green lacewing eggs have a stalk to protect the developing larvae from other predators. Brown lacewing eggs do not have a stalk. Lacewing eggs hatch in 3-6 days. Lacewing larvae look like small alligators and have large-sickle shaped mandibles that are used to catch prey. Larvae pierce the body of prey and suck juices. Green and brown lacewing larvae may look similar in appearance with 2 to 4 white spots on the top of body; however, the brown lacewing larvae have a side-to-side ‘head-wagging behavior’ that is not present in green lacewings. Besides aphids, these larvae can feed on whiteflies, caterpillars (fruitworms, loopers, armyworms), and even eggs. Each larva takes about 2 weeks to develop and may feed on 250-300 aphids per week. Green lacewing larvae pupate inside a cocoon attached to plant parts and adults emerge in about 2 weeks. Brown lacewing pupa is elliptical with a loose cocoon through which the pupa is visible. Lacewing adults are good fliers that are strongly attracted to light and can fly many miles immediately after emergence. Adult lacewings have delicate body and transparent wings with many veins visible (‘net-like wings’). Adults feed on pollen and nectar. Female lacewings can lay 200-800eggs and live for many weeks. The green and brown lacewings overwinter as adults but there are other species that can live as pupae during winter. About 2-3 generations may occur every year.

Larva with large
sickle-shaped mandibles
Eggs on stalks glued to a leaf
Pupation inside a cocoon occurs on plants

Adult lacewing with large wings
     
                  
   
           












Image sources: Oregon SU, University of Arkansas, Wikipedia, Iowa SU

Lacewing eggs can be purchased in large numbers from many suppliers. This approach to insect control is called ‘inundative biological control’ as pest management is expected from the released individuals. Alternatively, lacewing eggs may be released in an ‘inoculative approach’ where long-term establishment of the beneficial insect is desired. Due to rapid flight of adult lacewings out of their release site and lack of food, the inoculative approach may not always work on many farms. Therefore, some vegetable producers with high tunnels and greenhouses routinely use lacewings in conjunction with parasitoids for broad-based pest management. Identify the pest first and then purchase the appropriate predator.  [See Dr. McBug’s website for more information about how to keep these beneficial insects around].

Commercial lacewing eggs are packed in bran and the container can be kept refrigerated (not frozen) for several days. Do not transfer contents into another container for storage. Purchase eggs early in the week so they arrive in mail ready for release. A good practice is to check the viability of these eggs by retaining some eggs in a vial at room temperature and let them hatch in captivity. Eggs need to be scattered on plant surfaces while avoiding the presence of other predators like ants (please follow the instructions that come with your purchase). Manufacturers like Arbico Organics recommend 1000 eggs per 2500 square feet. Up to 50,000 eggs may be needed per acre for large scale release.

CONVERGENT LADY BEETLE
This is a very common species of lady beetle among the numerous others present in any crop field. The conver-gent beetle is common in Alabama and also very popular beneficial insect sold by companies, hence is worth discussing here.

The insect name comes from the two white lines seen on the thorax of adult beetles (arrow in picture) that seem to be coming together on the top. The number of dots can vary from none up to 13, so counting the dots alone is not a good identifier for this beetle. Larvae are black with rows of orange spots. Not that the lady beetle larva have chewing mouthparts and do not have the sickle shaped mandibles of the green lacewing larva (previous page). Eggs are elliptical and bright yellow in color; eggs are laid in clusters on plants with over 10 eggs per cluster. Eggs can also be laid in soil or plant debris. Pupae are immobile (nonfeeding stage) and may be seen stuck to plant parts.


Eggs on plant surface
Larva
Pupa
Adult lady beetle
          
                                                                                                       
 Image sources: Univ. of California—Davis, Iowa SU

Adults and larvae feed on aphids. Adult beetles also feed on nectar and pollen. According to industry sources, each adult lady beetle can destroy about 5000 aphids while the larvae can consume nearly 400 aphids in a week. In the absence of aphids, convergent beetles can also feed on moth eggs and small caterpillars. Female convergent beetles lay up to 1000 eggs in ideal conditions and have a lifespan of 1 to 3 months. Larvae feed for 3 weeks and adults emerge 2 to 5 days after pupation. Adults do not fly if air temperatures are below 55F. There can be many generations of this insect every year.

The presence of a large number of lady beetles can indicate the presence of aphids. This insect can be the most abundant predator in cotton fields. Many suppliers sell lady beetles in the adult stage when they are ready for field release. The adult beetles can also be stored in their original package for some duration. Industry sources recommend the release rate of 4500 beetles for 2500 square feet and much larger numbers for large areas. Out migration of adults once prey numbers dwindle is a major cause of loss of these powerful natural control agents. Routine release of beetles in large numbers can be effective in enclosed structures for aphid control.

I will continue to update this discussion of natural predators from the next issues of the IPM newsletter. Remember that parasitoids and pathogens also act in conjunction with predators to provide natural control of pests. Do your own research before purchasing large batches of predators and carefully plan the release for the best effect. Follow the instructions that come with your purchase of beneficial insects. Providing cover crops or shelter plants during fall season is a good way to facilitate continuity of predators in an area.  

In addition to the AL IPM Communicator, below are some very good resources on designing a farm system that attracts and maintains beneficial insect populations.

Additional Resources on Ecological Pest Management

In addition to the AL IPM Communicator, below are some very good resources on designing a farm system that attracts and maintains beneficial insect populations.

How to Get Started with IPM—Planning, Planning, Planning (excerpts from Biointensive Integrated Pest Management):


Good planning must precede implementation of any IPM program, but is particularly important in a biointensive program. Planning should be done before planting because many pest strategies require steps or inputs, such as beneficial organism habitat management, that must be considered well in advance. Attempting to jump-start an IPM program in the beginning or middle of a cropping season generally does not work.
IPM options may be considered proactive or reactive. Proactive options, such as crop rotations and creation of habitat for beneficial organisms, permanently lower the carrying capacity of the farm for the pest. The carrying capacity is determined by factors like food, shelter, natural enemies complex, and weather, which affect the reproduction and survival of a species. Cultural controls are generally considered to be proactive strategies.

The second set of options is more reactive. This simply means that the grower responds to a situation, such as an economically damaging population of pests, with some type of short-term suppressive action. Reactive methods generally include inundative releases of biological controls, mechanical and physical controls, and chemical controls.

Proactive Strategies (Cultural Controls)
  • Healthy, biologically active soils (increasing belowground diversity)
  • Habitat for beneficial organisms (increasing aboveground diversity)
  • Appropriate plant cultivars

Maintaining and increasing biological diversity of the farm system is a primary strategy of cultural control. Decreased biodiversity tends to result in agroecosystems that are unstable and prone to recurrent pest outbreaks and many other problems.  Systems high in biodiversity tend to be more "dynamically stable"—that is, the variety of organisms provide more checks and balances on each other, which helps prevent one species (i.e., pest species) from overwhelming the system.

Creation of habitat to enhance the chances for survival and reproduction of beneficial organisms is a concept included in the definition of natural biocontrol. Farmscaping is a term coined to describe such efforts on farms. Habitat enhancement for beneficial insects, for example, focuses on the establishment of flowering annual or perennial plants that provide pollen and nectar needed during certain parts of the insect life cycle. Other habitat features provided by farmscaping include water, alternative prey, perching sites, overwintering sites, and wind protection. Beneficial insects and other beneficial organisms should be viewed as mini-livestock, with specific habitat and food needs to be included in farm planning.

Examples of how to use farmscaping effectively in your farming system can be found in the references below.  Green lacewings and convergent ladybeetles are generalist predators that feed on a variety of pest insects so they are good beneficial insects to keep around your crops.  Appendix A in Farmscaping to Enhance Biological Control lists plants that attract beneficials.
 
To attract and conserve green lacewings, plant members of the carrot family (caraway, Queen Anne's lace, tansy, dill, angelica), sunflower family (coreopsis, cosmos, sunflowers, dandelion, goldenrod), buckwheat, corn, and provide water during dry spells.

Convergent lady beetles:  Once aphids leave a crop, lady beetles will also.  To retain active lady beetles , maintain cover crops or other hosts of aphids or alternate prey.  Plant members of the carrot family (fennel, angelica, dill, tansy, Queen Anne's lace), sunflower family (goldenrod, coreopsis, cosmos, dandelion, sunflower, yarrow), crimson clover, hairy vetch, grains and native grasses, butterfly weed (Asclepias), black locust, buckwheat, euonymus, rye).

Note from Appendix A that these same plants attract a large variety of beneficial insects.  Also note that these farmscaping plants are already present in most diverse organic agroecosystems as herbs, cut flowers, or cover crops.  By allowing some of these crops to flower they can serve double purposes in your cropping system.


Beneficial organisms should be viewed as mini-livestock, with specific habitat and food needs to be included in farm planning (ATTRA).

Grow Your Own Bugs:  Managing For Beneficial Insects or Plant It and They Will Come!
For information on how you can attract and maintain populations of beneficial insects in your gardens and fields visit the website of Dr. Richard McDonald (aka Dr. McBug):  www.drmcbug.com.

Click on the links at the top of the page for pictures and information on pests, beneficials, and farmscaping plants (plants for the purpose of attracting beneficial insects), epm (ecological pest management), and other valuable sources of information.

Farmscaping for Insect Management: Integrated Parasite/Predator/Pathogen Management & Strategies for Encouraging Beneficial Insects in the Field or "if you plant it, they will come...." Richard McDonald, Ph.D., Symbiont Biological Pest Management, 194 Shull's Hollar, Sugar Grove NC 28679;(828) 297-BUUG (2884); e-mail: the_edge@goboone.net website: www.drmcbug.com. 

Below are excerpts from Dr. McBug’s website:

Farmscaping Dr. Robert BUGG - Definition: Deliberate use of specific plants and landscaping techniques to attract and conserve "Beneficials". Feed your bugs - Dr. McDonald's Applied Farmscaping Principles:

1) Farmscaping is part of a Multiple Redundant Systems (MRS) approach - MRS is a form of disaster preparedness - triple redundancy is desirable for plants and insects. So for both you want "guilds" of food plants and natural enemies to protect your plants. This is why we list more than 10 beneficial food plants per season - more than one natural enemy attacking each life stage is better, too. Less can lead to breakdowns.
2) Anticipate Pest Problems - Think Ahead - encourage the right beneficial insects to be there when you need them to attack the pests. Ladybugs/trichogramma wasps attack the eggs of caterpillars.
3) Specific Plants attract specific beneficials - example: fennel is great for attracting parasitic wasps, syrphid flies, and ladybugs. So one plant can bring in a guild of beneficials.
4) 5-10% of crop area should be planted in farmscaping plants- "lots of clumps of food plants spread out over an area is much better than one big clump"!
5) Consider Dispersion indices for insects when foraging - "Insect Specs":

Low Dispersion- (Stay in field)
Medium Dispersion (forage 1/4 mile)
High Dispersion (forage > 1/4 mile)
Ground Beetles (Carabids)
Ladybeetles (when happy)
Most Parasitic wasps
Predatory Wasps - Paper
Syrphids - Hover Flies
Dragonflies, Tachinid Flies
Smaller Parasitic Wasps
Predatory Bugs
Larger Parasitic Wasps

6) Have something blooming all the time - Flowers are prime food & mating sites for wasps. Important to have a well fed, mated female beneficial! Green House - use to Jump-start garden areas.
7) Nectar - liquid sugar food + vitamins for beneficials. Nectar is critical for optimum performance of many beneficials. Many beneficials will lay over 3-fold more eggs if properly fed. Example: Parasitic wasps egg laying capacity - poorly fed - 30 eggs; if she is well fed, over 300 high quality eggs. Some of the best plants you can have for this purpose are those in the wild carrot family (also known as Umbellifera), such as dill, fennel, tansy, queen Anne's lace, caraway, coriander, parsnip, etc.
8) Extra-Floral Nectaries - nectar glands that are not associated with flowers. Peonies, Sweet potatoes, bachelor buttons, all have extrafloral nectaries. Parasitic wasps and flies use these extrafloral nectaries as important food sources.
9) Pollen - Is an alternative form of protein. Once again, many plants in the wild carrot family can provide pollen. Another good pollen producer is the corn plant. Syrphid flies need pollen to lay eggs.
10) Overwintering sites for beneficials - It turns out that many beneficials make cocoons and hibernate in or very near the plants where they find their hosts. Recent research has shown that yarrow and comfrey are also excellent overwintering plants for parasitic wasps.
11) Entrainment - (entomologists- Joe Lewis really opened up this field) have discovered that insects (especially parasitic wasps and flies) can perform associative learning, so if you get insects (especially young ones) happy in their environment, they will "tune in" to a particular pest. A good way to do this for a predator or parasite is to release it on or nearby the intended prey.
12) Drought/Stress - These systems can also fail! In drought years insects from all over will come to your area and can overwhelm a system. Be ready with backups additional insects,ladybugs/lacewings, Bt, soaps, diatomaceous earth. Save the soap/de for last, because they kill anything. Finally,
13) Your Design Decisions Mantra: Encourage Biodiversity! - Remember that insects are part of the web of life in your garden or farm. The beneficial insect complex is not only composed of parasitic wasps and flies, predatory beetles, lacewing larvae, ladybugs and so on, but ALSO the pollinators, antagonists/competitors that occupy and compete for space and food with potential pests, and finally the saprophytes and decomposing insects that help complete the food cycle back to the soil so the cycle can start again. And remember, "If you plant it, they will come...." For further information on Farmscaping, go to my web site (www.drmcbug.com) and click on the farmscaping section. Also see ATTRA's Farmscaping publication at their website (www.attra.org).

The gist of this message is that, just like us, beneficial insects need sources of food and shelter in order to stick around. You can weave "web of life" in your garden/farm by planting specific plants that attract specific beneficials. Also, by thinking ahead and anticipating the types of pest problems you might have, you can encourage the right beneficial insects to be there when you need them to attack the pests. My motto is: "If you plant it, they will come. Or, I will buy them (beneficials) once and have them here forever after..."

FARMSCAPING - Top Plants for Beneficials 
Spring: brassicas - ground ivy, wild mustards, Tulip poplar, vetches, pussy willow, yarrow, umbels - parsley/parsnip/ coriander, buckwheat, clovers, mints, Norway Maple, grains, peonies, borage.
Summer: mints, wild carrots- cow parsnip, tansy, bronze fennel, smartweed-Vietnamese Cilantro, Jerusalem artichoke, kenafe, sweet potato, borage, smartweed, bachelor buttons.
Fall: Patrina, Autumn joy sedum, vetches, chrysanthemum (Pacifica), tansy, bronze fennel, Queen Anne's Lace/other wild carrot family plants, garlic chives, Goldenrod, yarrow, comfrey and some of the last broccoli for overwintering on/underneath.

Top Beneficials
1. Ladybugs 2. Predatory Bugs - Big-Eyed/Nabid(Damsel)/Assassin/Stink/Pirate(Orius) Bugs. 3.Syrphid Flies 4. Parasitic wasps 5. Lacewings 6. Parasitic flies 7. Ground beetles 8. Spiders 9. Mantids 10. Dragonflies

Common Pests that we can control:
1. Whiteflies 2. Flea beetles 3. Spider Mites 4.Cucumber beetles 5. Aphids 6. Japanese beetle/Exotic scarabs 7. Squash Vine Borers 8. Cabbage Caterpillars 9. Mexican Bean Beetle 10. Stink bugs

Other resources for Ecological Pest Management:
USDA Alternative Farming Systems Information Center:


Biointensive Integrated Pest Management:  National Sustainable Agriculture Information Center:

Farmscaping to Enhance Biological Control:  National Sustainable Agriculture Information Center:  https://attra.ncat.org/attra-pub/summaries/summary.php?pub=145

Saturday, January 21, 2012

Local vs. Organic? What about both?

Which is best:  to eat locally grown or organic?  This question is often put forth as a choice that the consumer must make.  It is a false dichotomy similar to the choice that is often fabricated between the environment or the economy.  The truth is that they are usually both possible; in fact neither is a good choice without the other.  


There are many advantages to eating locally grown.  It is good for your health in that the food is usually much fresher and therefore higher in nutrients.  It is good for the economy of the community because it keeps food dollars in the local economy rather than exporting them to other parts of the country or even the world.  It is better for the environment because it does not have the footprint of transporting food from far away places and because small farmers, such as most of the produce farmers of Alabama, usually are better stewards of the land than large farmers.  They do not usually spray their fields aerially, contaminating large areas, non-target organisms, and bodies of water with pesticides.  They do not plow and leave bare large fields.  They usually do not use genetically modified seed, which has the potential of contaminating their neighbors' crops.


There are also many advantages of eating organic.  It is good for your health because there is no danger from pesticide residues on your produce.  Read:  "Three Studies Confirm Bad News About Insecticide Exposures" on the Georgia Organics website.  There are no worries about the effects of consuming antibiotics and hormones in your meat.


Rather than choose between buying from your local farmer or going to Wal-mart to buy certified organic produce why not just ask your local farmer to grow organic?  The major obstacle to the availability of locally grown organic produce is the lack of consumer demand, which can be attributed to the lack of consumer education.


It is often not just a matter of peeling your conventionally grown produce or washing it to remove pesticides.  According to The Organic Center:   


"About 20% of currently registered pesticides are called systemics. Systemic pesticides move into the plant through the root system, travel throughput the plant via its vascular system (plant blood, in effect), and move into surface tissues, where they either stop viral pathogens from growing or kill or repel insects. Some pesticides are 100% systemic, others are partially systemic."  Systemic pesticides are not only passed on to the human consumer, but also kill many pollinators, such as honeybees and butterflies.


The indiscriminate use of antibiotics to fatten food animals (cows, pigs, and chickens) and grow them faster favors the evolution and spread of antibiotic resistant bacteria, a serious threat to public health.

Beef cattle are implanted with hormones at the feed lot, and often on family farms as well, in order to fatten them up in record time and increase profits.  Dairy cows are given growth hormones to increase milk production.  Though the scientific verdict on the safety of consuming these hormones by humans is still out, the European Union has banned the production and import of hormone-treated meat, allowing only imports certified as produced without the use of hormones.  This has caused an on-going and acrimonious trade dispute between the U.S. and the European Union.  See: The U.S.-EU Beef Hormone Dispute.  The U.S. maintains that there is no scientific evidence that growth promoting hormones fed to food animals pose any danger to the consumer.  However, the EU maintains that scientific data on the safety of growth hormones is inadequate, and therefore further studies were needed; that controls necessary to ensure safe administration of the hormones were not in place in the US; that the ban was justified by the EU’s historical use of the “precautionary principle”, a simple belief that any potential risk to human health warrants caution.  The EU approaches risk assessment differently than the US. See:  "The Beef-Hormone Dispute and its Implications for Trade Policy".  


The United States is the only developed nation to permit humans to drink milk from cows given artificial growth hormone.[2] Posilac was banned from use in CanadaAustraliaNew ZealandJapan and all European Union countries (currently numbering 27), by 2000 or earlier 1


The American Public Health Association policy statement on rbGHUse in Dairy Production:  Since 1994, recombinant bovine growth hormone, also known as rbGH or rbST, has been injected into dairy cows to increase milk production; the hormone typically increased production by an average of 11 to 15%.36 rbGH was developed and marketed by Monsanto and sold to Elanco, a division of Eli Lilly, in October 2008. Although approved by the FDA in a November 1993 decision, both Canada and the European Union in 1999 refused to approve the drug’s use, officially citing harm to cows’ health.  No significant scientific studies since then have led these bodies to reconsider their stance. Australia, New Zealand, and Japan have also prohibited the drug’s use.
Although some studies (including several funded by Monsanto) have failed to demonstrate that rbGH harms dairy cows, virtually all independent analyses of the data reached a different conclusion. In addition to the Canadian and European studies, the FDA’s analysis of the data submitted by Monsanto demonstrated that use of rbGH increases the incidence of 16 different harmful conditions in cows, including birth disorders, hoof problems, heat stress, diarrhea, increased somatic cell count, and mastitis, a painful udder infection. On the basis of this evidence, the FDA requires these risks be listed on rbGH package inserts, but not on finished dairy products. Virtually all animal-welfare organizations, including the Humane Society of the United States and the Humane Farming Association, oppose the use of rbGH.

The use of rbGH presents an additional risk to human health in the form of antibiotic resistance. As more cows develop mastitis caused by rbGH use, farmers necessarily increase their use of antibiotics to treat the udder infections. There is now a consensus among scientists that antibiotic use in farm animals increases antibiotic resistance, which can then be transmitted back to humans through food or in the environment. Reducing rbGH use would serve to reduce antibiotic use in dairy cattle.

Scientific committees for Health Canada and the European Commission have also raised concerns about the potential effects of rbGH on cancer. Insulin-like Growth Factor-1 (IGF-1) is a necessary growth hormone present and identical in both cows and humans. However, elevated IGF-1 levels in human blood are associated with higher rates of colon, breast, and prostate cancers. On the basis of data submitted by Monsanto, FDA determined that rbGH use raises levels of IGF-1 in cow’s sera and cow’s milk. These data also show that IGF-1 survives pasteurization. Animal models show that most IGF-1 in cow’s milk survives digestion, reaching the bloodstream where it may promote cancer. The United Nations’ main food safety body, the Codex Alimentarius Commission, determined in 1999 that rbGH could not be declared safe for human health.

More and more US public health organizations have taken formal stances opposing the drug, including Oregon Physicians for Social Responsibility, Health Care Without Harm, and the American Nurses Association. In the last 3 years, more than 260 US hospitals have signed a pledge committing to serve rbGH-free dairy products.

A 2008 national poll showed that more than 90% of consumers favor labeling of rbGH-free products. Responding to this concern, many large retail establishments—including Wal-Mart—have phased out their milk brands produced using rbGH. Milk and many other dairy products from cows not treated with rbGH are now widely available; rbGH use fell from 22% of US farms in 2003 to 15% in 2007. Use of the synthetic hormone is still common practice on many large dairy operations, however. In 2007, nearly 43% of large herds were treated with rbGH.

In February 2007, Monsanto appealed unsuccessfully to the FDA and the Federal Trade Commission to restrict the labeling of rbGH-free milk. Since then, policymakers in 8 states have attempted to ban or restrict the labeling of rbGH-free dairy products through bills or administrative rules. All failed except in Ohio, where the proposed rules are being challenged in court.
Medical authorities and foreign governments have documented scientific public health concerns associated with rbGH use. As long as the FDA allows rbGH to remain on the market, consumers should have the right to know if it is present or absent in dairy products they consume. This right to know about hazardous or controversial substances has been defended in APHA Policy 2002-5.65 


Growth hormones are illegal for use in poultry production.  Antibiotics and arsenic are often fed to increase growth, but the rapid growth in today's chickens is attributed to selective breeding, improved nutrition, and protection from environmental stresses.


These growth hormones, antibiotics, and chemicals, such as arsenic often end up in the environment.  When they contaminate bodies of water, and adverse affects on fish populations.


If you have never watched some of the movies that describe the lives of animals that live in cafos (confined animals feeding operations), you should.  Food, Inc. is a good one.

The link between pesticide ingestion and elevated cancer occurrences are often hard to establish because of the time required for the cancer to develop and the many other factors involved.  Pesticide residues are often found in drinking water supplies and ground water.  Many pesticides are known to be lethal or harmful to pollinators, such as honeybees and butterflies, and to other non-target organisms as well.  According to EPA’s most recent Toxic Release Inventory (TRI) data, across the U.S. in 2010, 3.93 billion pounds of toxic chemicals were released into the environment, a 16 percent increase from 2009. The U.S. is rated 36th among 194 nations in longevity.  Obesity, stress, and toxic chemical exposure are among the factors responsible for the relative low rating.


By choosing organic, you are not contributing to this massive loading of our environment with toxic chemicals.  Locally grown organic is the best choice, not only for your health, but also for the environment.


Why is organic usually more expensive?  It is because of the higher cost of seed, soil amendments, and other farming inputs.  Also, organic requires more labor and labor is the most expensive aspect of farming.  Whereas conventional farmers can use chemicals to control weeds and pests, organic farmers must do many of these things by hand.  Organic farmers may also have more blemished produce that is unmarketable.  Consumers demand perfect-looking produce.  Why not demand naked produce instead?  Naked produce is that produced without the use of any synthetic chemicals.  It is chemical-free produce.

The NY Times recently published an article titled:  Organic Agriculture may be Outgrowing its Ideals.  It cited several examples of unsustainable organic agriculture.  By purchasing locally grown organic food you will avoid contributing to these unsustainable practices.  So vote with your food dollars: buy locally grown organic or better yet, grow your own.  If you have space in your yard, plant a garden.  It is a good way to get exercise, sunshine, entertainment, and education, as well as good food.  If you have a patio, plant in boxes or pots.  If you don't have space in your yard, join or start a community garden.  Then you can add "make friends" to your list of benefits of gardening.